


Atlantis, Baby!

by AnathemaAuthoress



Category: Rick and Morty
Genre: Anal, Belly Bulges, Bondage, Breathplay, Choking, Coercion, Cum Play, Drowning, Electrocution, Episode: s03e07 The Ricklantis Mixup, Hallucinogens, Incest, M/M, Masochism, Oral Sex, PWP, Plot What Plot/Porn Without Plot, Prostate Milking, Rough Sex, Sadism, Sex Pollen, Tentacle Monsters, Tentacle Sex, Tentacles, Urine, Watersports, cum surplus, dubcon, hormone hypnosis
Language: English
Status: Completed
Published: 2020-12-17
Updated: 2020-12-17
Packaged: 2021-03-10 16:48:56
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 8,082
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28120410
Author URL: https://archiveofourown.org/users/AnathemaAuthoress/pseuds/AnathemaAuthoress
Summary: Rick and Morty set off to explore the friendly deeps of the Lost City of Atlantis! Along the way they encounter a beast that seems to struggle to keep its tentacles to itself, but Rick and Morty find they don't really mind.
Relationships: Atlantis Monster/Morty, Atlantis Monster/Rick, Rick Sanchez/Morty Smith
Comments: 6
Kudos: 59





	Atlantis, Baby!

**Author's Note:**

> Originally intended for the 2020 minibang! Trouble irl made me miss the posting date, but honestly I'm just happy it's finally going up. Art included here was made for this fic by [KowaiSnail](https://twitter.com/kowaisnail) and [ PickleAki](https://twitter.com/PickleAki), in order that they appear. The story itself is based on [DevilishDaddy's](https://twitter.com/DaddyDevilish) art piece which is also included (smack in the middle of the other two). 
> 
> Thanks to everyone that kept me working on this! I hope you all like it!

“A fun, fresh, self-contained adventure,” Rick said shortly before opening up a portal and teleporting to a beautiful alien beachfront. 

The sands were almost crystal-glazed and milky white, and warm enough for the temperature to rise through Morty’s rubber flippers, but his focus was on the elegant, open scape of the ocean set before them.

The waves licked gently at the horizon, a calm and promising veil for what lie beneath. 

Morty loved the water and was surprised by how empty the beach seemed to be. It must have been a true nature-built place or it was off season for the locals.

“It’s so cool looking. Hey, Rick, come to think of it, how come we’ve never gone to the beach on Earth?” Morty fussed with the straps on his air tank as he spoke.

“Shut up, Morty, that’s an adventure for another day. Pay attention. Keep the mouthpiece in like I showed you. Goggles sealed?”

“Y-yeah,” Morty said excitedly as he double-checked the plastic suction around his eyes.

“Took the pressure pills I gave you?”

Morty stared off to the distance for a long instant, trying to recall.

“Seriously, Morty? Jesus Christ. You want the bends? ‘Cause if something happens, we gotta–we gotta come up real fast? You get the bends, air bubbles swell up in your idiot blood, fucking explode, fuck up your organs and soon you’re a–you’re a writhing mess, Morty! Is that what you want, Morty?” Rick’s eyes bulged and his voice rose in octave, partially reprimanding, partially alarmed.

“No!”

“No? No what, Morty?!”

“No, I don’t want the bends! Jeez, Rick! I took it, ok? I took–took it!”

“Fuck’s sake,” Rick growled. Then he seemingly returned to normal. “Okay and got everything else you need?”

“I think so.”

“Yes! Let’s do this bitch!” Rick put his own mouthpiece in place and led the way by wading forward and diving beneath the surface. Morty shuffled merrily out along the sands and belly-flopped and allowed himself to sink and follow after his grandfather.

For a while they just swam. Morty joyously watched schools of colorful alien fish as they rushed in swarms past him. He chuckled around his respirator when a small series of blue clown fish look-alikes swam under his stomach and tickled him even through his bodysuit. 

For once, Rick didn’t furrow his brow or chastise about having a good time, he just turned once in a while and waved to keep Morty moving forward.

Eventually, they drew close to the destination. Morty could see the inky black and icy blue spires of a fantastical city just on the horizon. Atlantis, just as Rick had promised. Morty had already started fantasizing about mermaids with long, sensual scaled tails and the torsos of human women. He hoped at least a few might resemble Jessica.

However, before they could get close enough to even see the gates, much less the mermaids, a powerful current rippled through the water. The first few waves were like a strong wind and Morty glided through the water off to one side, but was able to quickly right himself. However, before he could orient properly, another set of waves rushed through, stronger like the blow-off from seismic quaking.

“Hmmm!” Morty squealed around his mouth guard as he went spiralling, head over feet, off course. He looked beside himself and saw Rick toppling too, rolling as if they’d just fallen down stairs. 

The ripples blew them sideways from Atlantis, to the edges where light waters turned darker, high-density darkening the surroundings. 

The two were blown straight into a deep, cavernous gorge. At first, even once the spiralling had ceased and the water had stilled, it was too dark for Morty to make out his surroundings. Even so, he could see light trickling in from the exit and he moved toward it on instinct. He got just far enough for the light to lend credence to shapes and shadows. The walls of the gorge were formed of old dirt and coral compounds. They were craggy and gave the cavern a sort of imposing maw of faux teeth.

Morty looked to the side and saw Rick catching up to him—though not looking at him—and Morty continued to move. However, he halted promptly when the light ahead was overcast by a massive, squirming form and he saw what Rick had been seeing.

Morty gasped around the respirator and kicked his legs to draw back in the water.

As the shadow crossed the threshold and entered the cavern, its shape became apparent in the redirection of the dim sea light.

There, descending upon Rick and Morty at its apparent leisure, was a huge tentacled beast.

It took a moment for Morty’s eyes to adjust enough to take it in, but when he did he wished he had not.

It had the long, phallic head of a squid, but ordained with frills along the sides. Across its broad face it bore three eyes, evenly spaced, each glimmering toxic black even in the dark of the gorge. 

Its facial plane dripped down to a mouth which was broad like a glasgow grin and showcased rows and rows of shark-like incisors. It had long, thick tendrils with suckers along the bottoms, like an octopus, but with more limbs than Morty could count as it shuffled through the water, kicking up bubbles as it glided.

Between each tendril dangled more limbs, longer still and both rippled and frivolous, they swayed like papery things, jellyfish tentacles that seemed to shine with that same promising danger.

Upon seeing this great beast, Morty squealed, high and terrified like a little girl at her first scary movie. 

The sound was muted by the water and his breathing device. He hoped in a flash instant that they had gone unnoticed, but he had no such luck.

The long red tentacles extended out and, though they appeared to drift slowly, they were upon Rick and Morty before either could react.

An especially thick one wrapped about Morty’s slender hips until he was fully clasped in its grip. It gave a squeeze, not so tight it hurt, but firm enough that Morty could not wriggle free. His eyes grew wide and he struggled helplessly for a moment and pushed against the gleaming red flesh. It was more firm than he anticipated, with very little give.

Some of the long, silky jelly extensions came to join the sucker-lined tendril. They ran up and down Morty’s arms, made him flinch from the contact. Then the slender limbs slid beneath the edges of the boy’s diving suit and caressed his skin before sliding up to tear the fabric.

“Nhh!” Morty shrieked in alarm and looked frantically to where Rick floated, held aloft by a similar grouping of tendrils and gooey ribbons.

Fortunately, this time Rick was looking right at him and even in the dim light Morty could see his grandfather give the a-okay symbol. 

It meant this was safe, that Morty didn’t have to be afraid. This creature likely wouldn’t hurt them, it was okay to relax. 

The mere notion eased his nerves and he must have gone lax as a result because the monster loosened its grip and allowed Morty to float, though still entangled in tendrils, toward the outer edge of the cavern.

Morty watched the limbs now with fascination rather than fear. He pressed his hands to the gorge’s wall, against thick stones to steady himself. They were cold and gritty, texture like wrought iron. He braced and felt the lurid drawl of the tendrils along his skin. Compressing, ebbing, and flowing with a specificity far more direct than the surrounding waves.

More joined the first few and slid under his clothes and started to tug. Morty tried to reach his zipper, but before he could the limbs started to tear the fabric. Even under water he could hear the compressed ripping of the thick material. A jolt of excitement ran up his spine as his arms were freed to the water, then his legs in patches as suckers clung to the outside and yanked, leaving rips like moth-eaten holes in their wake.

Morty’s mind surged. Was this thing going to actually pleasure him? Was he going to accept it? It would not have been the strangest venture he’d ever had with Rick, but certainly one of the more pleasant. In the end, teenage hormones pushed out all other thoughts as the promise of getting laid rode high on the placcid waves engulfing him.

His body heated up as the tips of the tendrils danced over the surface of his flesh. They were slippery even under water and glided cooly along the surface of his pale body. One trailed over a nipple and the flesh hardened, stiffened to a pink peak under the teasing caress. Morty moaned around his respirator and his eyes rolled back.

He felt his cock hardening, and the monster noticed it as well. It snaked a thick tendril downward, to play along the tight wetsuit that still rested there. Morty’s cock bulged the fabric, made it outline his prick obscenely and tightened it so that his balls squished up against the drawn-up material, so those too bulged like a pair of too-tight gym shorts on some kinky Japanese anime character from Rick’s porn collection.

“Ohh,” he moaned and it continued to shimmy between his thighs. The slick friction felt maddening and Morty didn’t care if Rick was around, he was going to cum just like this, beneath the delicate touch of whatever squid-chimera-puss this creature was. 

Morty bucked shamelessly, encouraged further touch from the curious beast.

It obliged and two more tendrils, thinner than the first, but far meatier than the jelly frills, joined in to run the path up and down his sides. Exposed flesh felt different than the parts still covered, but each sensation was thrilling in its own right. 

They ran the gambit of his flesh, felt out the planes and valleys Morty had to offer. Every touch was tender, easy, like a lazy, lounging lover trailing fingers down his spine.

Morty was enjoying himself, feeling like he was edging closer to release, environment all but forgotten save for how the shudder of the water amplified his pleasure, when the monster got a bit too fresh.

He was leaned back, drooling about the cusp of his mouth piece, when he felt a thick extension squirm up the remnants of his suit’s leggings to prod at first one ass cheek, then the other, then the space between. 

Morty yelped in surprise and jolted a bit up the wall, but the tendrils followed. The one wrapped tenderly about his waist like a feather boa suddenly tightened more like the snake of the same moniker. 

Morty gasped at how the grip knocked the wind from him and he stilled so it would loosen again.

This seemed to work, but then that probing tentacle had returned to press along the satin groove of Morty’s boyish behind.

A sound like choking escaped Morty and he fidgeted once more and—once more—endured a warning squeeze. He shook his head, as if to indicate that he wasn’t interested in being penetrated. The beast either did not understand or else did not care. The tip of its limb first rubbed, dragging its gooey surface to wet Morty’s starburst of flesh at his opening, and then pressed inward until the tip of the red, waving limb was bulging just past the ring of muscle.

Morty’s pupils dilated and he started to thrash, not thinking of the consequences.

The sudden motion caused the beast to react with aggression. Met with protest, the smaller quivering extensions wrapped themselves about Morty’s wrists and ankles like rope, while the thicker masses gripped his center and pressed against his chest until his back dug into the fossilized wall.

This only made Morty foolishly panic further. He groped at the muscular tendrils and began to push roughly, not caring now if he hurt the monster in kind. He kicked, but his legs couldn’t go far in the restraints. His flippers were carelessly knocked off by the make-shift rope limbs and Morty’s toes flinched uselessly in the water, managing only to make little bubbles rise.

Morty tried to cry out for help, to get his grandfather’s attention, but the air in his mouth was serving as a necessary gag and his cries went unheard.

All the while, Rick was just fine. He was naked from stripping off his own diving suit. He had allowed it to float to the bottom of the cavern while his naked ass squirmed delightfully to the satisfaction of the sea creature. It had him wrapped up everywhere and he was joyfully suckling a particularly thick nub of flesh—respirator floating discarded at his hip as it dangled from his tanker—while his tongue worked against the edge of a suction cup, when he at last looked over and noticed Morty’s plight.

 _Eh, he’ll be fine,_ Rick decided for the time being. _A little rough play never killed anyone. Err, not anyone important._

As if sensing Rick’s flippancy, or perhaps he saw it in the glance that quickly passed, Morty offered up a middle finger from one of his restrained hands. _Fuck you, Rick,_ Morty thought as he realized he was going to have to endure whatever came next or fight for himself.

Once again, he took the route of a doomed man and continued to struggle twice as hard, determined to free himself before he was violated on terms he did not see fit.

He drummed up a bit of strength in his thin limbs and thrashed.

Taking the struggling as a challenge, the kinky beast tightened its grip further until its silken limbs were digging grooves that would surely bruise against Morty’s wrists and ankles. Then, doubling down, more jelly frills came to join in. They slipped under yellow pseudo-rubber neoprene and ripped and tore violently. They seemed to make a show of exposing Morty fully to the chilly waters. It didn’t feel so different, save for the mixture of humiliation and lurid waves rocking teasingly over strained skin.

Then, to punish Morty for his ongoing insolence, the frills drew back and snapped out, lashed against pert planes of skin.

Morty squealed again, high and pitiful, then jolted, nearly choked, as a strike was finished off with a hard electric zap.

Morty’s eyes looked down and watched as the bright light quickly faded to a light blue glow, then vanished, leaving only a harsh red mark on his skin in its wake.

“Fuunnghin eleecic?” Morty yelped around the respirator in alarm. 

The monster gave him one more strike across the chest for good measure. Then, despite the grips around his arms and legs, the touch returned to mercy-light caresses that contrasted sharply with the growing pain in Morty’s extremities.

The shocks, however, had only just begun. To Morty’s horror, a dozen or so frills lit up with static like poised tasers set to stun. They rolled over him with unexpectedly delicate fury.

They tickled along his skin like the kiss of raindrops, but the thunder and lightning that emerged from that dainty touch ripped through him like a storm. Electricity crackled forth from the limbs and burned a path along soft, peachy flesh. Morty’s body jerked, rigid and out of his control. Every limb strung taught, his teeth chattered. His cock bobbed in utter delight.

Each stroke was agony, but his body was a glutton for punishment and his prick began to leak. The tendons in his thin neck strained as he tossed his head back in a swell of pure pain and sensuality.

Even when the monster eased the voltage, got a taste for what the human treat could handle, Morty swore the jolts were like the stings of hornets, sharp and painful, with a throb that refused to cease.

They didn’t stop, refused to stop, until one fell along the curve of his cock. Morty’s chest heaved in frightened anticipation, and the payoff did not disappoint.

Morty nearly bit his tongue as the shock ran through his cock, shot through his testicles with a force he’d never felt before, and ripped his first orgasm from him in hard and unsteady pulses. He moaned and bucked his hips, throbbing, patternless circles, until the sputtering eased alongside the glow of the next series of jolts.

Morty tried his best not to heave around the mouthguard. He knew he wasn’t supposed to draw from the tank that way, but he couldn’t really help taking a few sharp, calming breaths. 

Just when he started to believe it was over, the jolts were replaced by suction. In circles his flesh was pulled tight as a tentacle unfurled down the path of his cock and clung by the cups. 

Morty whined, high and keening and not so uncharacteristic for him. His eyes flitted down to take in the sight, then drew back again as a powerful ache ripped up his prick. The tendril was tugging, pulling playfully but agonizingly against his cock flesh, far enough to threaten to tear, but not enough to do real damage.

The tip of the red limb, unfettered by the suction cups, slipped around the lip of the crown and pulled upward instead, effectively jerking the head off while the rest of the extension kneaded Morty’s cock.

He was oversensitive, unsure if he wanted more and more or nothing else at all. His skin prickled with goosebumps and he shook in the still too-firm hold of the beast. It was unrelenting and showed no signs of letting him go until it was good and ready.

With Morty momentarily placated by his eruption, the tendril teasing the rim of the boy’s ass decided to take another go.

The thick, slippery form wedged up into the tight hole and wriggled side to side to crawl into the hot cavern.

Morty’s expression grew alert once more and he moaned, low and rough, but his limbs were still held apart and he was weak from the electrocution.

Again he looked over to Rick and was shocked to see his grandfather was already fully speared, riding up and down on a thin sliver of monster flesh.

The sight sent another wave of warmth through Morty’s gut, this one unexpected and fire hot. For one moment that Morty would have thereafter denied, he became transfixed by the up and down bob of Rick’s untended cock. The long, terse flesh was twitching from the internal violation.

All the while, the tendril was going deeper into Morty, filling him out, spreading his insides. He’d had plenty of things smuggled up there before, but that was by his own hand. While seeds rubbing and rocking against his entrails was not without its charms, this was different, soft and intense, purposefully gliding along nerves to elicit a primal response.

Morty melted into the penetration, parted his own thighs further to finally accept it. He wasn’t getting out easily anyway so he figured he should try his best to _endure._

Besides, the feeling in his cock was too good to ignore, even when coupled with the growing ache of the penetration.

Morty contorted as his body was worked open. He could feel the tendril coiling inside, reaching places that were never meant to be touched. 

His heart pounded as the pain blended into the pleasure like some semi-sickening novacaine had been released into his blood.

As if he needed more to contend with, one of the tendrils which was not already presently occupied with rendering Rick and Morty to putty, crawled its way up Morty’s form and wrapped gently around his throat.

At first, the tickle of the suction cups made Morty nervous, but he didn’t preoccupy himself with too much concern, until the tip of the tentacle prodded against the edge of his snorkel.

Morty jerked his head back in a flinch. He was moaning around the bit between his teeth, and it made saliva pool under his tongue. However, he knew if it were to be removed he would promptly drown.

The monster of the deep seemed unconcerned about this potential plight, and pulled Morty closer and again probed at the breathing apparatus.

Then suddenly and with great force, the tendril cracked like a whip, startling Morty enough that it was able to wiggle its thin tip beneath the plastic. Morty felt the silky slick flesh crawl against his lips just before the snorkel was dislodged. 

The device popped free with little effort and began to float upward out of reach. Morty puffed his cheeks with his last inhale and tried to hold it as he watched his oxygen float away. He wanted to pull it back but his wrists were restrained. He still had the tank at his back, so it wouldn’t go far, but he still needed to retrieve the mouthpiece. 

As if reading his mind, the beast wrapped a spare tendril about the tank and tugged it free. The straps were not very strong and broke easily when yanked with the monster’s powerful limbs. Once it got what it wanted, it tossed the tank casually away and allowed it to drift uselessly to the ocean floor.

Morty’s eyes went wide in alarm and he started to whine through his shut lips in a feeble attempt to signal for help.

Almost at once, he started to twist his upper torso and grope with pinned hands for the objects now far beyond his reach. 

His held breath allowed him about a moment of rational motion, but the lack of air became too soon apparent.

It was becoming increasingly difficult to figure out what to do. Morty’s face darkened with flush and his chest began to tighten. He wriggled helplessly in the grip of the monster, but it continued to fuck him without any regard for his situation. In fact, Morty was certain it was trying to kill him, though that thought did little to diminish the pleasure pounding in and out of him. His head was swimming, floating lighter than his limbs in the water he was held fast beneath. His eyes tipped to the back of his head as he struggled to concentrate, to keep moans from erupting from clenched lips in a suicidal flurry.

He looked to Rick in a panic, but the old man was bent over, taking a railing which allowed little to no available wit for noticing Morty’s predicament. 

“Ngh,” Morty grunted without parting his lips. His body felt pulled tight, like a coiled spring, and he thought he might pop. His head screamed for him to open his mouth, but he denied it as long as he could. He tried to struggle free, but once more was held in place. He started to whine as the throbbing tentacle moved in and out, with increased speed. The beast was mocking him, _surely_ trying to kill him.

 _I knew one day Rick would fuck me over,_ Morty thought, with only the slightest twinge of humor.

Then no thought came, his eyes blew out wide, dilated so pupil nearly consumed iris altogether. The tendril slammed in so hard, and with such force that he was certain a fissure had been torn through his inner lining. His lips parted in a raw scream that came out silent and allowed a flood to surge into his open mouth.

Water had no hesitation. It burned through his nostrils, waterfalled down his throat. It seared like fire along his sinuses and forced him to gasp harder. This in turn drew more water inside.

Morty started to cry out, gasping erratically, unable to find any vestige of mercy in the cruel flood. His complexion darkened and his chest began to hiccup as his lungs filled with salty water.

His cock twitched on some pitiful reflex, his vision started to blur. He’d been through some horrible things, but he’d never drowned. It was like his body understood the gestures required to survive, but in so doing it sealed its own demise. The sharper the inhale, the faster his senses recoiled, leaving him dizzy and trapped. Panic hit harder than anything. His lungs spasmed, begged for breath, but only drew in more heat, more ache.

Bubbles rose from between his lips as the last of his carbon escaped and exploded like horrible mocking fireworks just above his head. 

The tentacles continued to caress his twisting, fading body with a sweet easiness that conflicted terribly with the pain and fear encasing Morty’s suffocating form. 

The one inside him, however, only amplified the more immediate sensations. It was grinding within him, turning and clinging, tugging his flesh almost cruelly. A suction cup glued to his prostate and ministrated there, all but vibrated and forced his cock to respond even in his utter terror. 

It all transpired in a matter of seconds and Morty knew he wouldn’t last long. He wasn’t sure if he was going to cum or die first, but either would be welcomed release from how the pressure gripped his lungs. It was too tight, too heavy, like being crushed.

The waves around him, already languid, seemed to slow and blur. His body leaned into the sharp pleasure instead of the pain. His chest went numb. He moaned in ecstasy as the dim undersea light started to fade. His spine arched in the tight wrap of the monster’s hold. His small body spasmed violently, he could swear he could feel bones cracking at how his body thrashed in need of air. The last thing he thought he would ever see was Rick’s blurry visage.

Yet then, that image began to clear.

Like a miracle, a light flooded his sight. In his woozy state, the teen thought perhaps an angel had swooped down to carry his soul away. Maybe she’d look like a mermaid with a halo to carry him to aqua nirvana, or maybe she’d be a classic angel, or the sort that might take a form like Jessica’s to see him to a higher plane. Morty had no way of knowing that what he was seeing was not divine intervention at all.

In fact, Rick had merely at last come to notice that Morty was on the verge of death. With some reluctance he had known he had to withdraw from the fun, if only for a moment.

He’d tried to politely dislodge, but the monster was a dedicated one. Annoyed, Rick had whipped out a phaser he kept on him anytime he traveled under the sea of any planet. 

He fired a warning shot, which illuminated the breadth of the dully lit cave and served two-fold to both partially blind and stun the Atlantis monster.

It worked splendidly and the octo-beast recoiled to shield its many eyes with the tentacles it had been using to violate Rick. It pulled out with a sticky plop that left Rick only disoriented for an instant.

Then, once he’d regained his bearings enough to ignore the sting in his gaping ass, Rick had swam quickly over. He didn’t have time for a fancy performance, so he retrieved an emergency tablet and placed it in his own mouth. He cracked it open between his teeth and–in a gesture he wrote off as a necessity–pressed his lips firmly to his grandson’s.

Morty’s mouth parted in a gasp as he inhaled the pill powder and the flavor of Rick’s low-grade whiskey.

Once he was medicated, Rick pulled back, allowing their lips to linger for only a second, and jabbed something between Morty’s exposed pectorals.

A piercing pain shot through Morty’s chest and he gasped, inhaled more water than any mortal could surely endure, and relaxed as his lungs regulated. “Wha-what?”

“Better, Morty?” Rick asked as he hovered nearby. 

His grandson stared back in disbelief, for a brief instant Morty forgot there was a tendril wriggling in his ass. “Y-you can talk underwa—but why did…”

“Spit it out, Morty, fuck.”

“W-why in the hell didn’t we just–why weren’t we using these to start with?!” Morty screeched indignantly.

“Because I didn’t want to hear you running your mouth all the way down here, Morty. Maybe sometimes I like to just, you know, enjoy the beauty of nature, _Morty._ ”

“Why are you like this?!” Morty wailed then gasped as the probe inside him shifted hard and made the sensation impossible to ignore. His eyelids drooped to half-mast and his lips parted, but for a long moment nothing escaped but moans.

Rick grinned wickedly at Morty’s slutty expression. Then he reached out to casually yank off the useless goggles from Morty’s expressive face. “So, good now? Yeah?”

“Huh? Wha—no!” Morty shook his head to regain his senses. “No, I’m not good! Get us out of here!”

Rick sighed as a tendril wrapped around his hips roughly. “Really? You don’t want to finish first?” He gave the tendril an apologetic caress and it seemed to slightly ease its hold.

Morty was flabbergasted. “Nooo—oh, ohh—no!”

“Oh fine,” Rick conceded, brandishing his weapon again. This time the beast of the deep was faster. It whip-cracked the device right out of Rick’s hands and it floated down to the sea floor, far out of range.

Rick’s eyes were wide in genuine surprise. “Oh, uh, oops.” Then he was yanked, hard and violent, back over to the limbs he had left behind.

Morty squirmed, both in arousal and terror. The feelings blending in his bulging gut and he let out a whimper. 

“Seriously, Rick?! What the fu—“ Morty’s words were blotted out as another extension swerved up through the water and clamped down over the teen’s mouth. Morty’s brows wove in confusion and annoyance. “Heeee!”

The tendril drew up, ran a path over Morty’s pink lips teasingly, soft enough to tickle. Before Morty could express his confusion in words the tendril pushed forward roughly and parted that soft mouth.

Morty’s jaw was forced open as the limb wiggled inside. The tendril was slightly fishy, but otherwise mostly tasteless, but the weight of it was heavy on Morty’s tongue. He gagged a bit as it moved to the back to rub along the ridges of his molars.

“Mmm,” Morty moaned helplessly as the monster pushed in deeper from both ends.

Morty thought he might die. His air was cut off a second time. It hadn’t been his imagination, the creature was suffocating him on purpose! It was worse now, with it probing deeper, pushing its girthy path through his windpipe to prevent oxygen from any outlet. It caressed the back of his tongue, laid heavy at the front and forced saliva to pool around it that Morty could not swallow.

Morty’s eyes began to water as it pumped, drawing back enough to let him gasp before plunging back inside to fuck his throat open.

His cock was drooling too, freeing threads of spider-silk white into the water as suckers plucked hickeys onto the pale canvas.

His ass was squelching, tensing and trying to fight off the invasion, but the monster was no longer moving at a languid pace. It drew back and slithered back in like a cobra charging at prey. Morty felt the relaxing ease of the release, then the all-consuming burn as an ungodly amount of flesh and muscle rammed it way deep into his svelte form.

Morty’s fingers flexed and trembled, groped helplessly for anything to grab onto. His ass shivered around the tendril ramming in and out. His cock was impossibly hard. He couldn’t breathe so every pulse inside made his lungs hiccup, but he had no way to release the air with the other arm of the beast blocking up his windpipe and smothering his nose as it crawled playfully around his face, squishing his cheeks mockingly as the monster fucked Morty to his limits.

At first the horror was such that Morty wanted to keep fighting, but after a moment of slick probing, rubbing against hot, secret places inside him, gagging and rolling spit down his throat, he became caught up in the rhythm, the vibration like a beat to an incredibly catchy song.

He bucked his hips as best he could and started to ride it. Dark blotches flashed before his eyes as that tightness in his chest became panic and his brain screamed for a breath of the oxygen Rick’s little pills could convert from the water. Yet not a drop could get inside.

 _This is it, oh god, this is it!_ Morty wasn’t sure if his head was swimming with his certain demise or his climax.

The monster yanked his head back and Morty arched his spine and he swore he could feel the two tendrils touch inside of him.

Shakes rattled through him. He became like a champagne glass in a storm, rattling, reverberating surrounding sound, squealing and spilling wine in splashes.

His hips buckled and cum flooded the water. The monster drew in a watery breath and sucked the flavor into its fanged maw. 

Rick was coming undone too. He was bent over with dozens of limbs wrapped around him, dark marks painting his body everywhere, thick sack bouncing enthusiastically as he came into the water.

The beast did not stop. Though it released Morty’s mouth at last, pulled from his throat soaking wet, dripping in threads of connecting saliva.

“Ahh!” Morty’s voice was deeper, ragged from overwork and the burn in his throat. He gasped in the water, relished in the cooling fluid that filled his lungs with needed air.

He didn’t have time to rationalize or calm himself though, just went straight from the sucking and gagging to gasping and keening and crying out for mercy.

His cock was all but limp for less than a second before the relentless, crushing drag of the tentacle in his ass stirred his prick back to life.

The silky wraps about his cock began to burn as they overworked the tissue.

Rick and Morty had inhuman libidos—Morty was uncertain if it was genetic or genetic mutation—but in any case, the teen still needed recovery time. The beast was insatiable, intent to pump him like an old fashioned water well, content to forcibly pry loose every last drop.

Morty’s tongue pressed lazily to the back of his teeth as his mouth gaped and his eyes rolled to the back of his head. “Oh! Oh!” His cock twitched, the crown was too dark, blood pounding there like in his heart. His sack had nothing left to give so his bladder filled in.

Without meaning to, Morty fell victim to the warm arms in the cold water and a hot yellow stream of piss shot out into the ocean. It stirred up bubbles in a wave, and speared into a line of pooling color before dispersing into the ocean to vanish.

The tightening in his stomach, the hot thrill of it left Morty whimpering, tugging and trying to curl in on himself to protect his sensitive place. His knees bent inward as he tried to shield his shame.

It was humiliating and intoxicatingly hot. He slammed his eyes closed, but still could feel Rick looking at him. He’d caught the old man’s attention and Rick was better at multitasking than Morty was. He could take in a show while being manhandled.

The monster gave the poor prick a few more languid strokes and Morty hitched in water on each pass, too tender but unable to escape.

The beast drew one more burst of urine forth before it slid up and plugged the eye of the cock to keep Morty from letting off again. Then the focus was back on fucking the teen.

“G-god, please, no more,” Morty whined. Tears formed on the lenses of his eyes then became one with the water all around. He was aching all over, he could feel his pleasure in every nerve, and he no longer meant what he pleaded for. Rick could tell, he knew that desperate, faraway glaze, so he didn’t worry too much about executing a rescue.

The beast continued to fuck them until the world around Morty seemed to be nothing but bubbles, the rawness in his throat, and the throb in his core. He needed it now, the harsh plunging, the scrape of jelly-thick material gliding effortlessly back and forth against his prostate. 

Just when he thought he couldn’t take anymore, Morty felt the bulge inside of him tug loose and the tendril slide free, leaving his ass gaping and shuddering. He felt empty, but his swollen inner walls were quick to bloat up in compensation, full of hot swimming blood cells. His entrance bloated as the flesh swelled up like rising bread.

“Ngh, come back,” Morty groaned on reflex.

The monster had other plans for the horny boy and dragged over a drooling, glazed-eyed Rick. Then, to both men’s surprise, the beast changed its grip to a loose wrap and wobbled them about like a child with dollies.

“Agh! What the hell?” Morty rasped as he was swiveled about, his insides quivered and sloshed uncomfortably with the motions. Then he was pushed flush against his grandpa’s chest. 

Rick was shockingly warm and the touch of him made Morty draw a gulp of surprise.

“Ah, shit, it wants us to kiss,” Rick said. He blinked a few times to fully gather himself and gripped Morty’s shoulders to keep the monster from slamming them together a second time. 

Instead, the beast smooshed them together with a deep purring sound. It rubbed them slightly up and down, forced their exposed, previously plugged cocks to slide along thighs and slant stomachs.

“Fuck,” Morty moaned. He was still shaken and barren from the loss of the tendril inside him. He didn’t have the wherewithal to think about all of the implications going on between he and Rick. The older man’s body felt so good, warm and tacky with fiction. He felt almost like the only real thing among the textures of fluidity and scaleless, satin-marbled fish flesh.

A tendril curled under them and lifted Rick’s cock and sack and bumped them against the curve of Morty’s ass crack.

“Wha-what do we do, Rick?” Morty was bright-eyed and alarmed, his expressions clear even in the dim of the cavern.

“Ah shit—ah ‘kay. Listen, Morty. We gotta see this through. It’s gonna be fine. We’re just gonna fuck a little bit,” Rick replied.

“E-ex-fucking-cuse me?!”

“Chill out, Morty. Just be—be cool. We don’t want piss this guy off.”

“Screw that, Rick! I don’t want to—to—“ Morty’s protests melted into fresh groans of pleasure as more tendrils began to need his cheeks and part them. He could feel his grandfather’s thick, ridge-rippled cock rubbing against his swollen entrance. The girth was firm, but malleable and soft, flesh old and slightly overused. The little bulges of the member were haunting as they bobbed along the terse edges of Morty’s asshole.

He was insanely turned-on. If he hadn’t already been captured in a haze of lust, he would have been then. Rick and he were nipple to nipple, chest to chest, as Rick’s cock bobbed under Morty’s seat. 

He had a crush on his grandfather, and though they’d tandem-fucked a number of creatures in their brief years together, getting it on together was not typically on the menu. Not beyond the occasional frottage at least. A full-on fucking might remove deniability. If Morty had _nothing_ else, he could rely on his denial.

Rick seemed less concerned, so maybe it was fine. Maybe it was all fine. Maybe it was actually the hottest thing Morty had ever considered. Maybe he wanted it, then and there.

Yet, maybe he only thought that because the monster had opened up its mouth and released a strange pink particle in the water. Rick and Morty breathed it in and relaxation filled their limbs. Rick’s eyes got huge and wide, sparkles seem to set in them.

“Ooooh, yeeeeeah, Morty. Cthulhu here just hit us with the good shiiit! Brace your ass!”

Morty started to laugh at the ridiculousness of his grandfather, and also at the stars that seemed to spring from the whites of his eyes.

Had Rick’s eyes always been whole galaxies? Morty leaned in, mouth pulled up in a dopey smile. He felt like he was falling, pooling into liquid space.

A thousand hands—or just ten fingers—wrapped around his ass and further parted his form.

The sensation was full-bodied, mentally electric, like the jolts of the jelly tendrils. Morty tilted his head back a bit and Rick started to reform in wavy lines of the water. He was like an old cartoon, eyes too big and lively, face stretched out, every peak of hair like spires to infinity.

Morty’s body _was_ the water and he wobbled with it. He felt it coming into him, being part of him. Then it was dancing at his lips, slipping inside to cover his tongue. It was unsurprisingly wet. Everything was wet, but this was sticky, and flavorful, full of unfamiliar samples of sharp and sour.

Morty had never been so turned on in his life. He felt like he was shaking with the hum of his desire, going so fast he might project out of his body. His body, which now seemed to him to be made of long threads of taffy. His own limbs were squid-like, extending out into the abyss, embracing Rick’s jelly, unfurling presence.

He was bouncing. Higher, higher into some unknown vortex where everything was suction. He vaguely heard his own cries. Then made out an undercurrent of deep and breathy groans that echoed endlessly in his mind and reverberated with hard thwacks of longing and want. Not his sounds, but Rick’s.

“More, more!”

Rick was happy to oblige. Less susceptible to the spray of pheromone, the world sort of wavered like the sidewalk on a hot day, but it didn’t bend and erupt like Morty’s reality. Rick’s body felt it in full force through, the strong race of blood in his nethers, the animalistic craving. He drove his cock deeper into his grandson, just high enough not to care. It felt fucking incredible. Tight and hungry. Morty was pretty, back arched, facial features soft as his mouth hung open in pleasure. Rick held him tight as he drove in with very little direction from the tendrils caressing his spine.

It was hard to move at full speed under water, but Rick managed, drove his hips piston-quick. His long cock was sucked all the way into Morty’s youthful form. “That’s it, baby,” Rick growled. “Cum for me.”

It repeated like a mantra in Morty’s headspace. He let off to it on the final chorus song. He tightened his hold on Rick’s shoulders, buried his face into the old man’s shoulder and sobbed as his body was utterly destroyed by spasms. He couldn’t stop, could only ride the thundering earthquake as his cock sputtered ropes of completion into the water

“Mnn, ngh, Ri-iiick,” Morty whimpered.

Rick almost felt bad for him. Not because he’d just gotten railed by his grandfather, that was awesomely hot, but because Rick could see the monster had at least one more round in store for them. The damn thing was grinning fin to fin.

“Hold onto me, babe,” Rick muttered. He kept his arms around Morty as his cock slipped free, limp and world-worn. He could easily go again, but he worried it might be Morty’s limit.

A moment later the tendrils were around them, cocooning them as the two men were coaxed into one last go.

The monster’s long reach dipped inside them both, opened up fuck-tight tunnels until they were pressed together, both crying out like bitches in heat.

This time the monster was merciless. It drove the limbs in and out lightning fast, unconcerned with fucking them into oblivion. The flesh squashed and stretched, doled out thin, then plunged in deep until the skin was folding over itself, muscle squashing to fit in as much as possible. Thin stomachs bulged huge with penetrating force. Morty thought he was going to puke as the world settled back into his vision, but he held onto Rick and let himself enjoy it instead. It felt weirdly good, a pleasure only not-quite-human men like them could enjoy. For Rick it was just enough, that sort of high he loved to chase but could rarely find short of fucking a hivemind—or his grandson, but that flavor was different.

The finale came in demon bursts of cum. The two huge tendrils fucking them weren’t the same as the arms before. They were long, projected cock coils. When the monster came, a boiling rush of creamy spunk came plowing into Rick and Morty’s bodies. It doused them, painted their insides creamy white. The milky mess sprayed hard out and around the intrusions as they became too full to contain it.

Their bellies got impossibly thick with it, the shapes laid bare and quivering, round wobbling in waves, as the hosing went on and on. 

“Ugh, nah!” Morty babbled. His pupils were pin lights, barely visible and his wit was gone. He could only feel, not think, and his body shook with unrestrained violent passion as cum filled him to the bursting point.

“Han! Hahg!” Rick tried to hold his composure, but it was gone. His nails worked marks into Morty’s arms as he held on for dear life.

The monster pulled out and drew up its tendrils. With a wild, sonic screech it sprayed another gallon or so directly onto Rick and Morty.

It blasted hard, made their tender skin jolt from the impact. It clung to hair and faces, limbs and stomachs. It glued them together, even in the water. Even what dispersed was quickly replaced as they were drowned in fresh mess.

When the sputtering stopped, the monster lowered them gently to the cavern floor beside what scraps of their gear remained. It brushed the cum from their noses and mouths so the forming bubbles could pop and they’d be able to breathe.

Then, like a booty call, it turned and left them there.

Morty watched it swim away with a vague sort of longing right before he blacked out.

When he came to, it was to the slightly painfully rubbing of hands on his face.

He opened his eyes with a groan and swatted the hands away. “Ugh, stop it!”

“Stop bitching, Morty,” Rick laughed. “Got to get you, uh, a-aaall cleaned up.”

Morty sat up and a mixture of pain and pleasure-sick nausea rose in his gut. “Oh, god, is it gone?”

“Y-yeah,” Rick said with a roll of his eyes. 

“That was—damn. That was crazy, Rick.”

“Y-yeah, well, that’s Atlantis mermaids for ya,” Rick said with a shrug as he helped wipe more spunk from Morty’s shoulder into the water.

“I’m sorry, what? Th-that thing was a mermaid?!” Morty stared off toward the cavern exit in disbelief.

“For fu—yes! Morty, damn when will your preconceived, retro-graded human expectations ever fucking cease?! It’s a Quali. Half Quali half mer-thing. It’s a mermaid! A merlad, maybe, who cares?”

“Relax, Rick,” Morty grunted. “I was just, you know, surprised.”

“So, I guess, you uh, probably want to leave and never return?”

“What, nah! I mean. Well, I mean it wasn’t _that_ bad,” Morty hurriedly corrected his own excitement.

Rick smiled, slow and accusing. “Shiiit, you like that mermaid cock, M-morty? You like taking that big ole mermaid schlong?”

“So did you!” Morty said quickly, face red with embarrassment. Now he was trying to pull off the sticky goo too. 

Rick started pulling out gadgets from seemingly nowhere and mended their suits.

“No shit, Morty. I’m not ashamed of that, don’t try to inflict your insecurity on me.”

“Oh, r-right,” Morty conceded. “So, um, we can do this—again maybe?”

Rick snorted back a laugh. “Yeah but we need like a code so your mom and sister don’t catch wise and make it weird. If anyone asks, we got us a ton of mermaid puss. Sweet, hot merm puss. Retain your little bitch dignity and keep Summer from asking me for gross shit. Deal?”

Morty smiled. “Yeah! I sure, sure did love that mermaid puss!”

“Yeah, mermaids, man, insatiable!” Rick jested. They started their swim back to shore, joking about their adventure all the way through the portal home.


End file.
